Help! External HDD partiton recovery

Posted by: caincha

Help! External HDD partiton recovery - 01/27/13 10:06 PM

Well, a few months back I had to sell my 2008 iMac (C2D w/ Snow Leopard) because I was moving to somewhere 3.000 miles away. No biggie, I had everything on my 3tb external HDD and I can always buy another Mac.
Which I did, I bought a Powerbook G4 1,67ghz since I was on a budget and needed a laptop.

The thing is, once I tried to use Tiger to repartition my external HDD like I used to do with Snow Leopard, it's partition table got screwed up! After some reading on the web I found out Tiger's partition scheme is different but it was too late.

So I tried some demos I've downloaded for this task and one of them asked for me to reformat the HDD. Why not, a quick reformat won't really erase anything as long as I don't rewrite it and restore it's partition, right?
Well, that app didn't restore anything and now I have a blank 3tb HDD...

Since then (almost a month now!) I've been trying anything I can get a demo of the web: Stellar, iPartition, DiskDrill, Disk Warrior, TechTool, Data Rescue, FileSalvage, Yodot, etc. None seems to do what I want, which is to restore my partition table.

I even tried Test Disk and some Windows alternatives like Partition Guru, Data Recovery HFS+ and like the others I tried on my Mac the closest I got was to recover the files, but I don't have a 3tb HDD to backup the first one - some apps did recover it raw, but I don't even know what to do with 2tb of raw data.

Anyway, what I want is to recover my HDD's partition table like it was before all of this, any suggestion?
And why is it so hard to do with HFS+? Some 10 years back I had a similar accident with my Windows desktop and could undo it in a matter of hours including the time I spent looking for answers on the web...
Posted by: MacGizmo

Re: Help! External HDD partiton recovery - 01/28/13 08:25 AM

I'm confused. Are you actually trying to recover the files that were on the drive before you reformatted it? If so, you can stop trying, because it's not going to happen unless you spend about $1,500 at DataDoctors or some other specialized service. Reformat means completely erase, then reallocate the blocks of the drive for new use–which pretty much kills any chance of file recovery.

If you're simply trying to repartition the drive, you should be able to use Apple's Disk Utility app to completely reformat the drive and re-partition it. Notice I didn't say "restore." You aren't going to be able to restore anything, because there's nothing there to restore.
Posted by: six_of_one

Re: Help! External HDD partiton recovery - 01/28/13 08:36 AM

Agreed.

"Why not, a quick reformat won't really erase anything as long as I don't rewrite it and restore it's partition, right?"

Unfortunately, that really, really lessened the chances for a full recovery ...
Posted by: caincha

Re: Help! External HDD partiton recovery - 01/28/13 11:41 AM

I already did recovered a few files that I needed ASAP (work-related) and at that time I could see/access everything else, but it was read-only so I needed another 3tb HDD, which I don't have.

I don't know if anything changed in the last few years but as far as I know reformatting doesn't really erase anything: http://en.wikipedia.org/wiki/Disk_formatting#Reformatting
Posted by: Jim_

Re: Help! External HDD partiton recovery - 01/28/13 01:58 PM

There is no utility for HFS to recreate the partition map like you can with MBR (FAT-NTFS). Your only hope at this point is to use what you used to recover the work files and transfer them to another drive. Also at this point since you've been messing with the formatting so much there is probably no viable backup directory on the drive either for data recovery apps to parse file types etc.

Sorry to hear of you predicament. All I can suggest is next time don't mess with partition tables unless you have a backup of the drive. I would never consider any major maintenance without a backup.
Quote:
The thing is, once I tried to use Tiger to repartition my external HDD like I used to do with Snow Leopard, it's partition table got screwed up! After some reading on the web I found out Tiger's partition scheme is different but it was too late.
Just curious, what did you use to do that? iPartition?
Posted by: NucleusG4

Re: Help! External HDD partiton recovery - 01/28/13 06:05 PM

Originally Posted By: MacGizmo
I'm confused. Are you actually trying to recover the files that were on the drive before you reformatted it? If so, you can stop trying, because it's not going to happen unless you spend about $1,500 at DataDoctors or some other specialized service. Reformat means completely erase, then reallocate the blocks of the drive for new use–which pretty much kills any chance of file recovery.

If you're simply trying to repartition the drive, you should be able to use Apple's Disk Utility app to completely reformat the drive and re-partition it. Notice I didn't say "restore." You aren't going to be able to restore anything, because there's nothing there to restore.


I think that's a full wipe. A quick wipe will just delete the directory. Some scavenging apps may be able to recover some files... but it's hit and miss.
Disk Warrior used to be the tool for scavenging a drive without a directory.
Posted by: caincha

Re: Help! External HDD partiton recovery - 01/28/13 07:47 PM

Originally Posted By: Jim_
Just curious, what did you use to do that? iPartition?
No, I used Disk Utility. smile

From 10.5 onwards you can repartition easily with no hassle and I thought I could do the same on 10.4
Posted by: Jim_

Re: Help! External HDD partiton recovery - 01/28/13 08:19 PM

Originally Posted By: caincha
Originally Posted By: Jim_
Just curious, what did you use to do that? iPartition?
No, I used Disk Utility. smile

From 10.5 onwards you can repartition easily with no hassle and I thought I could do the same on 10.4
In your OP you said; "The thing is, once I tried to use Tiger to repartition my external HDD like I used to do with Snow Leopard, it's partition table got screwed up!" It didn't screw it up, it did what you told it to do.

It wasn't Tiger. Anytime you use DU to repartition it deletes the catalog. It even warns "Partitioning this disk will delete all the data on this disk." DU has never been able to repartition with destroying everything.

I feel your pain, but just wondering why you tried anything with the external, especially since it was your only data source, maybe I missed something.

I just noticed that you partitioned it then reformatted it. Both steps make it harder to get files recovered. Without getting into the way the HD stores its catalog, I know just enough to get it but not explain it correctly, when you erase the drive and delete the catalog it still has info stored on what was there. Every time you do something destructive it gets rid of more the cookie crumb trail it has left.

I hope anything you lost can be recreated, IOW no pictures etc.
Posted by: NucleusG4

Re: Help! External HDD partiton recovery - 01/29/13 04:12 AM

Yeah... looking backwards... he should have cloned his disk to another drive first. Even if it meant finding someone else who had a computer.
Posted by: caincha

Re: Help! External HDD partiton recovery - 01/29/13 03:56 PM

Originally Posted By: Jim_
It wasn't Tiger. Anytime you use DU to repartition it deletes the catalog.
Sorry, but you can do a non-destructive repartition with Disk Utility on Leopard, Snow Leopard, Lion and Mountain Lion without losing anything at all.
But if you do that on Tiger you're screwed, that's my point.

About the issue itself, I'll keep on looking to see if I can actually fix this the way I want (and won't be using that HDD until then). If not, I'll buy another HDD, what the heck... frown
Posted by: MacBozo

Re: Help! External HDD partiton recovery - 01/29/13 05:12 PM

Originally Posted By: caincha
Originally Posted By: Jim_
It wasn't Tiger. Anytime you use DU to repartition it deletes the catalog.
Sorry, but you can do a non-destructive repartition with Disk Utility on Leopard, Snow Leopard, Lion and Mountain Lion without losing anything at all.
But if you do that on Tiger you're screwed, that's my point.

About the issue itself, I'll keep on looking to see if I can actually fix this the way I want (and won't be using that HDD until then). If not, I'll buy another HDD, what the heck... frown


Disk Utility in Lion:

Posted by: Jim_

Re: Help! External HDD partiton recovery - 01/29/13 07:44 PM

You can enlarge a partition in DU by deleting one and adding it to the rest of the drive, but other than using BootCamp I don't know of a way to make smaller partitions without being destructive
Posted by: caincha

Re: Help! External HDD partiton recovery - 01/30/13 05:41 AM

Originally Posted By: Jim_
You can enlarge a partition in DU by deleting one and adding it to the rest of the drive
As it seems (read it on the web) 10.5 -> 10.8 uses GUID and 10.4 uses Apple, that's why it got screwed up in my case...